The production of lithium  an essential ingredient in batteries for electric cars  has become easier and significantly cheaper, thanks to a technological breakthrough, just as US concerns about China's dominance in the supply chain are on the rise. The cost of extracting the mineral has been slashed to a "record low" of 15,000 yuan (US$2,180) per ton by the new process, a Chinese government report said. That compares to an international price for lithium ranging from US$12,000 to US$20,000 per ton  and a long-term contract price of about US$17,000  over the past year, according to some industrial estimates.